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<h4 class="subsection" id="MSP430-Variable-Attributes-1"><span>6.34.10 MSP430 Variable Attributes<a class="copiable-link" href="#MSP430-Variable-Attributes-1"> &para;</a></span></h4>

<dl class="table">
<dt><a class="index-entry-id" id="index-either-variable-attribute_002c-MSP430"></a>
<a id="index-upper-variable-attribute_002c-MSP430"></a><span><code class="code">upper</code><a class="copiable-link" href="#index-upper-variable-attribute_002c-MSP430"> &para;</a></span></dt>
<dt><code class="code">either</code></dt>
<dd><p>These attributes are the same as the MSP430 function attributes of the
same name (see <a class="pxref" href="MSP430-Function-Attributes.html">MSP430 Function Attributes</a>).  
</p>
</dd>
<dt><a id="index-lower-variable-attribute_002c-MSP430"></a><span><code class="code">lower</code><a class="copiable-link" href="#index-lower-variable-attribute_002c-MSP430"> &para;</a></span></dt>
<dd><p>This option behaves mostly the same as the MSP430 function attribute of the
same name (see <a class="pxref" href="MSP430-Function-Attributes.html">MSP430 Function Attributes</a>), but it has some additional
functionality.
</p>
<p>If <samp class="option">-mdata-region=</samp>{<code class="code">upper,either,none</code>} has been passed, or
the <code class="code">section</code> attribute is applied to a variable, the compiler will
generate 430X instructions to handle it.  This is because the compiler has
to assume that the variable could get placed in the upper memory region
(above address 0xFFFF).  Marking the variable with the <code class="code">lower</code> attribute
informs the compiler that the variable will be placed in lower memory so it
is safe to use 430 instructions to handle it.
</p>
<p>In the case of the <code class="code">section</code> attribute, the section name given
will be used, and the <code class="code">.lower</code> prefix will not be added.
</p>
</dd>
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